Control method, controlled device, user interaction device and computer program product

ABSTRACT

A method for controlling a controlled device is disclosed, wherein the controlled device has a host connection to an RFID tag, the method comprising the following steps: (s1) the controlled device writes operational parameters to the RFID tag through the host connection; (s2) a user interaction device reads the operational parameters from the RFID tag through an RFID connection; (s3) a user changes the operational parameters via a user interface comprised in the user interaction device; (s4) the user interaction device writes the operational parameters to the RFID tag through the RFID connection; (s5) the controlled device reads the operational parameters from the RFID tag through the host connection and adapts its behavior based on the operational parameters. Furthermore, a corresponding controlled device, a user interaction device and a computer program product are disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority under 35 U.S.C. §119 of Europeanpatent application no. 12163933.0, filed on Apr. 12, 2012, the contentsof which are incorporated by reference herein.

FIELD OF THE INVENTION

The invention relates to a method for controlling a controlled device.The invention also relates to a controlled device, a user interactiondevice and a computer program product.

BACKGROUND OF THE INVENTION

In recent decades numerous types of electronic devices have appeared onthe market with ever increasing functionality which has been enabled bya continued increase in digital processing capabilities. For example,energy-frugal sensor nodes enable securely logging and/or transmittingall kinds of sensory data, household appliances—such as for examplewashing machines and kitchen ovens—get more and more features to controlboth their primary process as well as their energy consumption, andelectronic watches and time-controlled electric plugs (also known astime switches) have a plethora of functions nowadays.

For many of these devices, their user interaction means have not kept upwith the increase in functionality. For example, an energy-frugal sensornode is very small and may not be able to accommodate more userinteraction means than just one or two buttons. Also, it is veryenergy-constrained and may therefore not be able to drive a display oreven just a few LED's. Electronic watches and time-controlled electricplugs do have a display, but typically have very few buttons to controltheir operation, making a simple task—such as setting the time—a tedioustask for many end-users.

There are prior art methods which control a first device by utilizinguser interaction means on a second device. For example, it is known fora UPnP device to expose a user interface to another UPnP device (see“Remote UI Client and Server V 1.0” by the UPnP Forum, retrievable fromhttp://upnp.org/specs/rui/remoteui/). UPnP devices are connected bymeans of a (wired or wireless) IP connection. Similarly, it is known fora computing device to take control of another computing device usingremote desktop protocols such as RDP and VNC (see “Remote DesktopProtocol” by Microsoft, retrievable fromhttp://msdn.microsoft.com/en-us/library/aa383015.aspx, and “VirtualNetwork Computing” by Wikipedia, retrievable fromhttp://en.wikipedia.org/wiki/Virtual_Network_Computing). These protocolsalso take place over a (wired or wireless) IP connection. Most of thesesolutions are primarily meant to enable controlling a device fromanother location. The controlled device may or may not have rich userinteraction means of its own, i.e. a local user interface.

Design constraints for a device—for example cost, form factor, powerbudget, or the physical environment that the device is to be deployedin—may limit the possibilities for user-friendly interaction with thatdevice. Specifically, it may not be possible to equip the device withrich user interaction means, such as a touch screen. Instead, the devicemay have been equipped with very simple user interaction means, forexample very few buttons which much be pressed in a specific sequence touse certain functionality on the device.

Interaction using such simple means is far from intuitive and may cause,at least, a lot of frustration and wasted time for end-users.Effectively, it may even mean that an end-user is not able to perform adesired task using the device at all. If the user would have had theability to control the same device with a rich user interface instead,such as a touch screen, he/she would have been able to complete thedesired tasks quicker, more reliably, and with less frustration. In thelight of the ever increasing functionality enabled by such devices, thisproblem will only intensify.

Existing remote user interface (UI) solutions (such as UPnP RUI, RDP orVNC) require a data connection to be established between the device tobe controlled and the device providing the user interaction means. Thismay be a wired or a wireless data connection (for example a Wi-Ficonnection). Establishing a wired or wireless data connection requiresadditional actions on behalf of the end-user and is often cumbersome.Furthermore, requiring a device to possess a wired or wireless interfacefor such a data connection may conflict with constraints such as lowcost, low power usage and/or small form factor.

SUMMARY OF THE INVENTION

It is an object of the invention to improve the user interaction withcontrolled devices which have constraints on their user interactionmeans. This object is achieved by a method as defined in claim 1, acontrolled device as defined in claim 12, a user interaction device asdefined in claim 14, and a computer program product as defined in claim16.

According to an aspect of the invention, a method for controlling acontrolled device is conceived, wherein the controlled device has a hostconnection to an RFID tag, the method comprising the following steps:(s1) the controlled device writes operational parameters to the RFID tagthrough the host connection; (s2) a user interaction device reads theoperational parameters from the RFID tag through an RFID connection;(s3) a user changes the operational parameters via a user interfacecomprised in the user interaction device; (s4) the user interactiondevice writes the operational parameters to the RFID tag through theRFID connection; (s5) the controlled device reads the operationalparameters from the RFID tag through the host connection and adapts itsbehavior based on the operational parameters.

According to an exemplary embodiment of the invention, in step (s1), ahost controller comprised in the controlled device writes theoperational parameters to the RFID tag through the host connection; andin step (s5), the host controller adapts the behavior of the controlleddevice by configuring a set of controlled functions based on theoperational parameters.

According to a further exemplary embodiment of the invention, the RFIDtag sends a wake-up signal to the controlled device upon a predeterminedevent, such that the controlled device wakes up from an off state orlow-power state.

According to a further exemplary embodiment of the invention, thepredetermined event is a detection of an RF field by the RFID tag or theestablishment of the RFID connection.

According to a further exemplary embodiment of the invention, thepredetermined event is the writing of the operational parameters to theRFID tag in step (s4) or the disappearance of the RF field or the RFIDconnection in step (s4).

According to a further exemplary embodiment of the invention, ahandshake protocol is executed between the user interaction device andthe controlled device via the RFID tag, such that the controlled devicemay return to the off state or low-power state if it does not need toperform a step of the method.

According to a further exemplary embodiment of the invention, thehandshake protocol comprises that the user interaction device changes asignaling flag comprised in the RFID tag; the signaling flag indicateswhether or not the controlled device needs to perform a specific step ofthe method; and, upon waking up, the controlled device reads thesignaling flag and returns to the off state or low-power state if thesignaling flag indicates that it does not need to perform any specificstep of the method.

According to a further exemplary embodiment of the invention, the RFIDtag only provides the wake-up signal to the controlled device ifpredetermined sections of a memory comprised in the RFID tag are readfrom and/or written to by the user interaction device; wherein thepredetermined sections of the memory contain operational parametersrelating to operations that require a wake-up of the controlled device.

According to a further exemplary embodiment of the invention, theoperational parameters include a description of the user interfacecomprised in the user interaction device.

According to a further exemplary embodiment of the invention, thedescription of the user interface embeds operational parameters whichdirectly relate to the functioning of the controlled device.

According to a further exemplary embodiment of the invention, thedescription of the user interface is provided by reference, inparticular by a URL pointing to a website from which the description ofthe user interface is retrievable.

According to a further aspect of the invention, a controlled device foruse in a method of the kind set forth is conceived.

According to a further exemplary embodiment of the invention, thecontrolled device is one of the group of: an energy-frugal sensor node,a household appliance, a time-controlled electric plug, an electronicwatch. According to a further aspect of the invention, a userinteraction device is conceived, in particular a portable userinteraction device, for use in a method of the kind set forth.

According to a further exemplary embodiment of the invention, the userinteraction device is an NFC-enabled smart phone or a web tablet.

According to a further aspect of the invention, a computer programproduct is conceived which comprises program elements executable by acontrolled device or a user interaction device, wherein each programelement comprises program instructions which, when being executed by thecontrolled device or the user interaction device, cause said controlleddevice and user interaction device to carry out or control respectivesteps of a method of the kind set forth.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in more detail with reference to theappended drawings, in which:

FIG. 1 illustrates exemplary embodiments of a controlled device and auser interaction device according to the invention;

FIG. 2 shows exemplary values or states of a signaling flag for use in ahandshake protocol according to an embodiment of the invention.

DESCRIPTION OF EMBODIMENTS

According to an aspect of the invention, a method is conceived whichenables a user to interact with a device (i.e. a controlled device)which does not comprise user interaction means, or which only comprisesminimal user interaction means. The method involves a second device(i.e. a user interaction device) which may comprise rich userinteraction means.

FIG. 1 illustrates exemplary embodiments of a controlled device 100 anda user interaction device 120 according to the invention. Effectively,the controlled device 100 and the user interaction device 120 form asystem in which the above-mentioned method can be applied.

The controlled device 100 comprises a host controller 112 and aso-called Connected Tag 102. A “Connected Tag” is defined as an RFID tagwhich has a host connection 116, i.e. a wired connection, to the hostcontroller 112. The Connected Tag 102 comprises a non-volatile memory104, a (passive) RFID interface 106 for contactless reading/writing ofthe non-volatile memory 104, a tag controller 108 for controlling thefunctions of the tag and a wired interface 116 with the host controller112 (i.e. the host connection) enabling the reading/writing of thenon-volatile memory 104 by that host controller 112. The controlleddevice 100 may for example be an energy-frugal sensor node, a householdappliance such as a washing machine or a kitchen oven, a time-controlledelectric plug or an electronic watch. The user interaction device 120comprises an NFC interface device or an active RFID device 122. The NFCinterface device or active RFID device 122 is able to read/write datafrom/to the Connected Tag 102, while supplying power to the ConnectedTag 102. The user interaction device 120 may, for example, be anNFC-enabled smart phone or a web tablet with a touch screen as userinteraction means.

An exemplary embodiment of a method according to the invention comprisesthe steps of:

(1) The host controller 112 of the controlled device 100 writes certainoperational parameters initially or regularly into the non-volatilememory 104 of the Connected Tag 102.

(2) The end-user brings the user interaction device 102 into closeproximity of the controlled device 100 and the user interaction device102 reads the operational parameters from the non-volatile memory 104 ofthe Connected Tag 102.

(3) The end-user interacts with a user interface 126 comprised in theuser interaction device 120, which results in new and/or updatedoperational parameters for the controlled device 100.

(4) The end-user brings the user interaction device 120 again into closeproximity of the controlled device, or, alternatively, it is kept inclose proximity during the whole procedure. Subsequently, the userinteraction device 120 writes the new and/or updated operationalparameters into the non-volatile memory 104 of the Connected Tag 102.(5) The host controller 112 reads the new and/or updated operationalparameters from the non-volatile memory 104 of the Connected Tag 102 andsubsequently adapts the behavior of the controlled device 100 based onthese operational parameters. It should be observed that steps (1) and(5) are executed under control of the controlled device 100, whereassteps (2), (3) and (4) are consecutively executed under control of theuser interaction device 120. It is not necessary for step (1) to beimmediately followed by steps (2), (3) and (4). Likewise, it is notnecessary for steps (2), (3) and (4) to be immediately followed by step(5). In other words, there may be an unspecified time lag between theexecution of step (1) on one hand and steps (2), (3) and (4) on theother hand. Similarly, there may be an unspecified time lag betweensteps (2), (3) and (4) on one hand and step (5) on the other hand.Furthermore, it is possible for step (1) to be executed multiple times,before executing steps (2), (3) and (4) or for steps (2), (3) and (4) tobe executed multiple times without step (1) being executed in between.Similarly, it is possible for steps (2), (3) and (4) to be executedmultiple times before executing step (5) once.

It is noted that instead of the non-volatile memory 104 another type ofmemory may be implemented on the Connected Tag 102. However, it isimportant that the contents of the memory can be retained when noexternal power is supplied to the Connected Tag 102. In particular, thenew and/or updated operational parameters should remain available to thehost controller 112 after disappearance of the RF field, so that thehost controller 112 may perform step (5) at any time. In principle thismay also be achieved with a volatile memory and a battery backup.

In short, the controlled device 100 does not have to be equipped withrich user interaction means, while it still enables rich userinteraction via the user interaction device 120. This reduces costand/or relaxes other design constraints for the controlled device 100.For example, the controlled device 100 has no room for a touch screen oris used in a harsh environment where the touch screen may get dirty oreven be destroyed. As a matter of fact, the controlled device 100 may becompletely stripped of any user interaction means, which further lowersits cost and further increases its design freedom. For example, anenergy-frugal sensor node according to an embodiment of the inventionrequires no buttons or LED's at all (it is even conceivable tocompletely mold it in Perspex, making it very robust against dirt andother environmental influences). Likewise, a household appliance ortime-controlled electric plug requires neither buttons nor a display andan electronic watch may require fewer buttons.

Compared to other remote user interface (UI) techniques utilizingwireless communications (e.g. UPnP Remote UI, RDP or VNC) theabove-described method lowers cost (a Connected Tag 102 is very costeffective), simplifies session setup (the user interaction device 120may simply be held close to the controlled device 100) and may evensupport interaction with the controlled device 100 whilst the latter ispowered down. Furthermore, the energy needed by the controlled device100 to accomplish the user interaction may be significantly lower as itneeds to power neither user interaction means nor a radio for wirelesscommunications. This is important if the controlled device 100 issignificantly more energy-constrained than the user interaction device120, for example, when a smart phone is used to configure anenergy-frugal sensor node.

In addition to the system elements introduced above, the controlleddevice 100 also comprises a host memory 110 used by the host controller112 and a set of controlled functions 114. The controlled functions 114embody any of the primary functions of the controlled device 100, forexample: sensors and storage and/or data transmission means in anenergy-frugal sensor node, motors, heaters and valves in a washingmachine, heating elements, fans and a microwave tube in a kitchen oven,relay and timing functions in a time-controlled electric plug, or timingfunctions in an electronic watch. The host controller 112 controls thesefunctions 114 in accordance with the operational parameters.Furthermore, the user interaction device 120 comprises a controller 124,a memory 128, and a user interface 126 (i.e. user interaction means).The controller 124 may execute a program element which implementsparticular steps of the method, i.e. steps (2), (3), and (4)) andutilizes the memory 128, the user interface 126, and the NFC interfacedevice or active RFID device 122 for this purpose. As an optionalfeature, a wake-up signal 118 may be provided. For example, uponinteraction of the NFC interface device or active RFID device 122 withthe RFID interface 106—e.g. to read from or write to the non-volatilememory 104 in general or from or to specific parts thereof—the wake-upsignal 118 is raised by the Connected Tag 102 to wake up the hostcontroller 112 from an off state or low-power state.

In the following paragraphs exemplary applications of a method of thekind set forth, i.e. of the exemplary embodiment of a method accordingto the invention, will be described. In particular, the controlleddevice for use in this method may be an energy-frugal sensor node, ahearing aid, a household appliance, and a time-controlled electric plugor socket.

Energy-Frugal Sensor Node

An energy-frugal sensor node is a device that measures one or morephysical quantities, for example, lighting level, temperature, airpressure, air flow, motion and concentrations of gases like relativehumidity, CO₂, CO, O₂, ethylene and volatile organic compounds. Itcomprises means to store and/or wirelessly transmit these measurementsfor further usage.

An energy-frugal sensor node typically operates in a duty-cycledfashion, i.e. waking up periodically from a very low power sleep modefor a very short period of time to perform and store/transmit somemeasurements and subsequently reverting back to the sleep mode. Thisduty-cycled operation makes the sensor node so energy-efficient that itcan live on a small battery for many years or can even harvest itsenergy from the ambient.

One example of an energy-frugal sensor node is a data logging device formonitoring the quality of perishable products (e.g. food or medicine).The device is attached to a pallet of products or even to an individualproduct (e.g. a milk carton) and logs the environmental conditionsduring distribution or even during the entire lifetime of the product.Inspection of the logs can be used to assess the quality of the product(e.g. remaining shelf life). It is obvious that cost, power, and formfactor constraints are so strict that the device cannot comprise rich(or even any) user interaction means. Using a low-cost Connected Tag ofthe kind set forth enables a rich user interaction on a user interactiondevice instead (even while the device is asleep or its battery isdepleted).

The user interaction could, for example, involve browsing the loggeddata, resetting the logged data when attaching the device to anotherpallet and modifying configuration settings such as the periodicity, theset of physical quantities to measure and the associated measurementaccuracies.

Another example is an in-body implant such as an intraocular implant ora subcutaneous implant that monitors and logs biologically relevantparameters in a human or an animal. Power and form factor constraintsare extremely strict and external self-powered user interaction isprobably the only possibility to read out and configure the implant.

Yet another example of an energy-frugal sensor node is a wireless sensornode applied in, for example, a building control system or forstructural integrity monitoring of constructions such as bridges. Inthis case, the measurements are transmitted periodically over a wirelessnetwork interface. Although the wireless network interface provides, inprinciple, means to remotely interrogate and configure the device, thismay be difficult in practice. In order to be sensitive to interrogationand configuration requests (e.g. read out the current sensor values, setthe periodicity or set the set of physical quantities and associatedaccuracies) the device must be in receive-mode permanently or at leastat well agreed moments in time. When the device is in receive-modefrequently, its energy reserves may be depleted quickly. When the deviceis in receive-mode very infrequently the interaction may have very longresponse times. Therefore, interaction by means of a method of the kindset forth enables low power usage while maintaining short responsetimes. Also, the wireless network interface may not be usable at allbefore the device is configured (i.e. chicken-and-egg problem).Furthermore, if this device is one of a plurality of similar devicesconnected to the wireless network, a method of the kind set forthenables very intuitive selection of this particular device—as opposed toanother device in the plurality—for subsequent user interaction bymerely bringing the user interaction device in its proximity.

Hearing Aid

Another example of a small form factor device is a hearing aid. It needsto fit in/on the auricle and, for aesthetic reasons, be as small aspossible, meaning that there is no room on the device itself for richuser interaction means. On the other hand, in order to personalize thehearing aid, a wide variety of audio parameters (e.g. amplification perfrequency band) needs to be configured. Furthermore, during a sessionwith the audiologist, small adaptations to the settings may need to bemade interactively. Providing rich user interaction by means of themethod according to the invention enables the audiologist to do his jobproperly and efficiently, while the small form factor (i.e. aesthetics)constraints are still satisfied. Similarly, the end-user of the hearingaid may need to change settings such as the volume or to enable aspecific mode of operation such as “speech-mode”, “music-mode” or“TV-mode” (i.e. using an inductance loop to pick up the TV sound). Alsothat is easily accomplished with a method of the kind set forth: tap thephone to the ear (i.e. hearing aid), change the settings on the touchscreen and tap it once again.

Household Appliance

Household appliances such as washing machines, tumble dryers, dishwashers and kitchen ovens tend to get more and more integratedfunctionality. As user interaction means not always scale up with thisincrease in functionality, the end-user experience may suffer.

For example, a washing machine, tumble dryer or dish washer offers awide variety of programs and may additionally have means to adapt itsschedule to variable energy pricing schemes. This means complex userinteraction may be required to use the appliance properly. Designconstraints may seriously limit the amount of space available forproviding user interaction means. For example, for aesthetic reasons, adish washer may have to be hidden behind wood paneling. As a result, theuser interaction means may end up on the top side of the door, that isonly a few centimeters high. A touch screen at that location is clearlyout of the question, not only for form factor reasons, but alsoconsidering the high temperatures and humidity it may be exposed to.Furthermore, the user interaction means are not accessible (or evenvisible) during operation of the dish washer, implying for example thatthe end-user is not kept informed about the progress of the dish washingprocess (e.g. time to completion). A method of the kind set forthprovides a convenient way to interact with the household appliance andchange its operational parameters.

As another example, a high-end kitchen oven offers a wide variety ofheating options (e.g. bottom heat, top heat, hot air, hot air formultiple layers, grill, microwave, steam, incineration cleaning and manycombinations and intensity settings thereof), time functions,pre-programmed preparation schedules, etcetera. Yet, such a kitchen ovenhas to fit a standard-sized kitchen cabinet. For example, a so-called“compact” oven has to fit a 560×450×550 mm3 (w×h×d) cabinet. Within thisform factor the actual oven cavity should have maximum dimensions to beable to prepare as much food as possible. This struggle for space can beobserved from the fact that appliance manufacturers have moved the usercontrol panel from the right hand side to the top side of the oven; awider, yet lower oven cavity being the result. Using a method of thekind set forth, a UI-less kitchen oven with a wide and high oven cavitycould be provided that can be conveniently programmed by means of a richuser interaction device such as a smart phone or a web tablet.

Time-Controlled Electric Plug or Socket

A time-controlled electric plug is a device that can switch mainspowered loads on or off based on a pre-determined time schedule.Typically it can be inserted into an electric power outlet and itcomprises an electric power outlet by itself to plug in the load.

For example, it is often used to switch lighting on and off in a home tocreate the impression that someone is at home to scare off potentialburglars (in this case, a partially randomized time schedule may beemployed). As another example, it can be used to switch heating devices(such as an electric water boiler or a waterbed) on only whenelectricity is available at a low tariff.

Anyway, time-controlled electric plugs are available on the marketeither comprising a mechanical clock or an electronic clock. In case ofa mechanical clock, it is programmed by means of putting pins in holesor by toggling mechanical levers. In case of an electronic clock, it isprogrammed by utilizing user interaction means, for example, a small LCDdisplay and a handful of buttons. The programming of such a prior arttime-controlled electric plug is often cumbersome. Having few buttonsimplies that very specific sequences of button presses are needed toaccomplish a certain task. In many cases these sequences are notintuitive and also the result of the task cannot be easily verified,just adding to end-user frustration. Furthermore, it is only possible toprogram the plug when it is plugged into a mains outlet (unless when abattery is inserted), which may be cumbersome if the plug is installedin a hard to reach place. And finally, even though the user interactionmeans are relatively limited, there is still significant cost associatedwith providing them.

According to an exemplary embodiment of the invention, thetime-controlled electric plug comprises no user interaction means, butonly a Connected Tag. This has a number of benefits:

(1) The cost of the plug can be lower, because the cost of a ConnectedTag is much lower than the cost of above-mentioned user interactionmeans.

(2) The form factor of the plug can be much smaller as no room is neededfor user interaction means; as a matter of fact the “plug” could becompletely integrated into a wall socket.

(3) The user interaction device provides much richer user interactionmeans (e.g. touch screen) making the interaction more intuitive andbetter to verify, thereby reducing the probability of end-userfrustration.

(4) If the plug is installed in a hard to reach place, user interactioncan still take place while holding the user interaction deviceconveniently in the palm of one's hand. Only the act of bringing theuser interaction device into close proximity of the plug requires accessto the plug itself, but this act is much simpler to perform in a hard toreach place (e.g. a dark corner in the back of a closet) than actualuser interaction.

User Interaction with a Controlled Device that is Switched Off

A method of the kind set forth also permits control over the controlleddevice 100 even while it is switched off. This is enabled by the factthat the Connected Tag 102 contains a non-volatile memory 104 and thatthe NFC interface device or active RFID device 122 comprised in the userinteraction device 120 is able to power the interaction with theConnected Tag 102. In this way, the controlled device 100 neither has tobe switched on all the time, nor does the end-user have to switch it onexplicitly before starting interaction (and switch it off again aftercompleting interaction).

Basically, step (1) of the method of the kind set forth is performed bythe controlled device 100 at a moment that it is active (i.e. switchedon), which may be different from the moment that user interaction takesplace. At some later moment, the controlled device 100 might be switchedoff and actual user interaction, i.e. steps (2), (3), and (4), takesplace. At yet a later moment, the controlled device 100 might be activeagain and take the changed operational parameters that resulted fromthis user interaction into account for its subsequent operation, i.e.the controlled device 100 performs step (5).

Clearly, it might be undesirable for a controlled device 100 to beswitched on all the time, because its power consumption could increasesignificantly. For example, an energy-frugal sensor node can onlyfunction if it only wakes up periodically for a very short period oftime. This is known as duty-cycled operation.

Similarly, it might be undesirable for an end-user having to switchon/off the controlled device 100 explicitly, as this may complicate theprocess of user interaction. Furthermore, in the case of theenergy-frugal sensor node, even the relatively short period that itwould be switched on (i.e. for the duration of the process of userinteraction) would be too long and deplete its energy reserves.

Wake up Host Controller During or Following Interaction

As explained above, using a method of the kind set forth enables userinteraction with a controlled device 100 whilst the controlled device isswitched off. Although this ability has clear benefits (i.e. lowerenergy consumption and/or simplified user interaction), it also hascertain drawbacks: (A) the operational parameters read from thecontrolled device 100 in step (2) of the method were determined the lasttime the controlled device 100 was switched on and (B) the updatedoperational parameters written into the controlled device 100 in step(4) will only influence the behavior of the controlled device 100 thenext time it is switched on. In other words, there may be a serious timelag between performing steps (1) and (2) and similarly betweenperforming steps (4) and (5). This means that the user interaction maybe based on ‘old’ operational parameters from the controlled device 100and similarly that the controlled device 100 may only act on the updatedoperational parameters significant time after the user interaction tookplace.

As a first example, if the controlled device 100 is an energy-frugalsensor node comprising one or more sensors and if its sensors'measurements can be displayed by means of the user interaction device120, the time lag between performing steps (1) and (2) may imply thatthe sensor values as displayed may be outdated.

As a second example, if the controlled device 100 is a washing machinethat is programmed by means of the user interaction device 120 to starta program at some future moment in time, the washing machine might onlybecome aware of this fact after the moment passed. The reason is thatstep (5)—setting a timer controlled by the washing machine's hostcontroller 112—is not immediately triggered by the occurrence of step(4); writing the new programming into the Connected Tag 102.

As a third example, if the controlled device 100 is a device comprisinga real-time clock—for example, a time-controlled electric plug or anelectronic watch—and if the user interaction device 120 is used to setthis clock to the correct time, the following might occur. As part ofstep (2) the user interaction device 120 would read the ‘current’ timethat was stored into the Connected Tag 102 by the controlled device 100a certain amount of time before that as part of step (1). Clearly, inthe mean time, this time is not correct anymore and only confuses theend-user.

A further exemplary embodiment of the invention, which will be describedin more detail below, enables steps (1) and (2) respectively (4) and (5)to follow each other instantaneously to avoid the drawbacks describedabove, while it is still neither necessary to keep the controlled device100 powered all the time, nor to have the end-user switch it on and offmanually. The optional wake-up signal 118 mentioned earlier plays apivotal role in this exemplary embodiment and is briefly explainedfirst.

Wake-Up Signal

The basic principle of the wake-up signal 118 is as follows. The wake-upsignal 118 is provided from the Connected Tag 102 to the host controller112 of the controlled device 100. When an NFC interface device or activeRFID device 122 interacts with the Connected Tag 102, the wake-up signal118 is raised and the controlled device 100 is woken up from its offstate or low-power state (i.e. the controlled device 100 is switchedon).

Different conditions may be used to the raise the wake-up signal 118. Inone variant the wake-up signal is raised when the appearance—or thesubsequent disappearance—of a field generated by an NFC interface deviceor active RFID device 122 is detected. In another variant the wake-upsignal 118 is raised only when that NFC interface device or active RFIDdevice 122 addresses this particular Connected Tag 102, i.e. uponestablishment of an RFID connection. In yet another variant the wake-upsignal 118 is only raised when the non-volatile memory 104—orpredetermined memory cells thereof—have been written to or read from (orboth) during the interaction. In other words, the raising of the wake-upsignal 118 may be triggered by a general or a more specific event on theRFID connection 130, e.g. the appearance or removal of an RF field(general event) or the reading from or writing to a specific memory cell(specific event).

Thus, according to an exemplary embodiment of the invention, the RFIDtag sends a wake-up signal to the controlled device upon a predeterminedevent, such that the controlled device wakes up from an off state orlow-power state. According to a particular exemplary embodiment of theinvention, the predetermined event is a detection of an RF field by theRFID tag or the establishment of the RFID connection. This enables thatthe controlled device is able to perform step (1) substantiallyinstantaneously before the user interaction device performs step (2).According to another particular exemplary embodiment of the invention,the predetermined event is the writing of the operational parameters tothe RFID tag in step (4) or the disappearance of the RF field or theRFID connection in step (4). This enables that the controlled device isable to perform step (5) substantially instantaneously after step (4).

FIG. 1 suggests that the wake-up signal 118 is fed to a pin of the hostcontroller 112 causing it to wake up from an off state or low-powerstate. However, alternatively, the power supply of the controlled device100 is disabled or disconnected in the inactive state and the wake-upsignal 118 pulls a switch, e.g. galvanic or MOSFET, to power thecontrolled device 100 to cause it to move to the active state. In thisway, the power consumption in the inactive state is zero, but no statecan be retained in the controlled device 100 (other than the state ofthe non-volatile memory 104). This implies that some startup time (boottime) is required before the controlled device 100 is fully functional.

It is noted that the use of a wake-up signal 118 from the Connected Tag102 may also be beneficial if the controlled device 100 is not switchedoff or in a low-power state. In this case, the wake-up signal 118 simplyserves as an interrupt signal to the host controller 112, triggering itto start executing a subsequent step of the method.

Handshake Protocol Using Signaling Flag

In order to make step (2) instantaneously follow step (1), the act ofbringing the user interaction device 120 into close proximity of thecontrolled device 100 (i.e. initiating step (2)) should trigger the hostcontroller 112 to wake-up and provide the operational parameters to theConnected Tag 102 first (i.e. executing step (1)) before proceeding withstep (2). In order to make step (5) instantaneously follow step (4), thewriting of the changed operational parameters into the Connected Tag 102by the user interaction device 120 (i.e. completing step (4)) shouldtrigger the host controller 112 to wake up, read those operationalparameters from the Connected Tag 102 and subsequently adapting itsbehavior based on these operational parameters (i.e. executing step(5)).

A further exemplary embodiment of a method according to the invention,which exhibits those features, is described below. This method makes useof different types of wake-up signals, varying from very specificwake-up triggers (e.g. a specific memory cell of the Connected Tag 102being written) to very generic wake-up triggers (e.g. an RF field orRFID connection 130 appearing or disappearing). It is noted that thedisappearance of the RF field or the RFID connection 130 may be a verynatural wake-up trigger for causing the transition from step (4) to step(5); the end-user is ready with the user interaction and removes theuser interaction device 120 from the close proximity of the controlleddevice 100, thereby removing the RF field and the RFID connection 130.

Effectively, a handshake protocol is executed between the userinteraction device 120 and the host controller 112 of the controlleddevice 100 via the Connected Tag 102. In order to track the differentstates of this handshake protocol properly, a dedicated memorylocation—i.e. a signaling flag—is allocated in the non-volatile memory104 of the Connected Tag 102.

FIG. 2 shows exemplary values or states of a signaling flag for use in ahandshake protocol according to an embodiment of the invention. In theexemplary method described below, this signaling flag may assume any offour values (states): “waiting for request” 200, “request parameters”202, “parameters available” 204 and “parameters updated” 206. In aninitialization step 208 the signaling flag is initialized with the value“waiting for request” 200.

Specifically, the writing of the signaling flag by the user interactiondevice 120 should cause the wake-up signal 118 being raised by theConnected Tag 102. Depending on the type of wake-up signal 118 used,other events (e.g. writing to another memory location, not being thesignaling flag or even the mere appearance or disappearance of a randomRF field) may cause the wake-up signal 118 to be raised as well. Theexemplary method described below is made robust against such “falsehits” by having the host controller 112 check the value of the signalingflag before proceeding with its next step. Although these “false hits”do not break the exemplary method as presented, they may cause morefrequent (and unnecessary) wake-ups of the host controller 112,resulting in unnecessary power consumption. In other words, having theConnected Tag 102 support more specific wake-up triggers enables areduced power consumption of the controlled device 100. For an energyfrugal sensor node, for example, this may be beneficial.

A further exemplary embodiment of a method according to the inventioncomprises the following steps (it is noted that steps (1) and (5) of theabove-described method are now split up in sub-steps):

(1a) The end-user brings the user interaction device 120 into closeproximity of the controlled device 100 and the user interaction device120 changes the value of the signaling flag in the Connected Tag 102from “waiting for request” 200 to “request parameters” 202, resulting ina first state transition 210.(1b) The Connected Tag 102 raises the wake-up signal 118 in response tothis interaction with the Connected Tag 102, the host controller 112wakes up and checks whether the signaling flag is set to “requestparameters” 202. If so, the host controller 112 proceeds with the nextstep. If not, the host controller 112 may return to the off state orlow-power state.(1c) The host controller 112 obtains or computes the operationalparameters and subsequently writes them into (another memory locationof) the non-volatile memory 104. Subsequently, the host controller 112sets the signaling flag to “parameters available” 204, resulting in asecond state transition 212.(2) The user interaction device 120 polls the signaling flag until it isset to “parameters available” 204 and subsequently reads the operationalparameters from the Connected Tag 102.(3) The end-user interacts with a user interface 126 on the userinteraction device 120 resulting in changed operational parameters (i.e.new and/or updated operational parameters) for the controlled device100.(4) The end-user brings the user interaction device 120 again into closeproximity of the controlled device 100—alternatively, it is kept inclose proximity during the whole procedure—and the user interactiondevice 120 writes the new and/or updated operational parameters into theConnected Tag 102. Then, the user interaction device 120 sets thesignaling flag to “parameters updated” 206, resulting in a third statetransition 214.(5a) The Connected Tag 102 raises the wake-up signal 118 in response tothis interaction with the Connected Tag 102, the host controller 112wakes up and checks whether the signaling flag is set to “parametersupdated” 206. If so, the host controller 112 proceeds with the nextstep. If not, the host controller 112 may return to the off state orlow-power state.(5b) The host controller 112 reads the new and/or updated operationalparameters from the Connected Tag 102 and subsequently adapts itsbehavior based on these operational parameters. Finally, the hostcontroller 112 sets the signaling flag to “waiting for request” 200,resulting in a fourth state transition 216.

In case the wake-up signal 118 is triggered by the mere appearance of anRF field or an RFID connection, the following race condition may occur:the wake-up signal 118 being raised by the appearance of the RF field orthe RFID connection and subsequently first the updated parameters andthen the signaling flag being written by the user interaction device120. As a result, in step (5a), the host controller 112 may check thesignaling flag just before it is actually set to “parameters updated”206 by the user interaction device 120 in step (4) and conclude that itdoes not have to proceed with step (5b). This race condition can beavoided by either the Connected Tag 102 delaying the raising of thewake-up signal 118 (e.g. by using an RC-filter) or by the hostcontroller 112 polling the signaling flag over a certain period of time(e.g. 100 ms). If the wake-up signal 118 is triggered by thedisappearance of the RF field or the RFID connection or by the actualwriting of the memory cell containing the signaling flag, then this racecondition does not occur.

Variants

It should be noted that many variants of the above-described furtherexemplary embodiment can be imagined. For example:

When it is necessary for step (2) to instantaneously follow step (1),but it is not necessary for step (5) to instantaneously follow step (4),only steps (1) and (2) comprise the use of the signaling flag. In thiscase the signaling flag may be two-valued.

-   -   When, reversely, it is not necessary for step (2) to        instantaneously follow step (1), but it is necessary for        step (5) to instantaneously follow step (4), only steps (4)        and (5) comprise the use of the signaling flag. In this case the        signaling flag may also be two-valued.    -   Alternatively, the handshake mechanism (including the        maintaining of its state as embodied by the signaling flag) may        be realized in dedicated control hardware of the Connected Tag        102. In this variant, the Connected Tag 102 provides the ability        to intercept a read attempt of the non-volatile memory 104 via        its RFID interface 106. When the user interaction device 120        attempts to read operational parameters, the Connected Tag 102        stalls the response to the user interaction device 120. In the        mean time it wakes up the host controller 112 by means of the        wake-up signal 118, the host controller 112 obtains or computes        the operational parameters and subsequently writes them into the        non-volatile memory 104 at which point the Connected Tag 102        completes the read attempt by providing the requested        operational parameters to the user interaction device 120. As a        matter of fact, intermediate storage of these operational        parameters in the non-volatile memory 104 is not even strictly        necessary for this variant. Alternatively, the read attempt        could be stalled by the dedicated control hardware of the        Connected Tag 102 by a fixed amount of time, while the wake-up        signal 118 is provided to the host controller 112. This fixed        amount of time should be sufficiently large for the host        controller 112 to wake-up, obtain or compute the operational        parameters and write them into the non-volatile memory 104. For        example, the amount of time may be 100 ms. However, it should be        noted that this variant is more complex, because the Connected        Tag 102 is no longer a relatively simple dual-ported        non-volatile memory 104—having an RFID interface 106 and a host        connection 116—with a wake-up capability, but a component which        requires more complex control circuitry.

Waking Up the Controlled Device Selectively

In the section “User interaction with a controlled device that isswitched off” it has been explained that in some cases it is beneficialto interact with the controlled device 100 while it remains switchedoff, whereas in the section “Wake up host controller during or followinginteraction” it has been explained that in other cases the controlleddevice 100 should be woken up prior to and/or directly following userinteraction.

It may happen that for a single application, some operations performedduring user interaction require the controlled device 100 to wake upprior to and/or directly following user interaction, while for otheroperations this is not necessary. This can be accomplished byconfiguring the Connected Tag 102 to provide a wake-up signal 118 onlyupon reading and/or writing operational parameters (i.e. sets of memorycells of non-volatile memory 104) relating to those operations thatrequire waking up. Obviously, the memory cell containing signaling flagis a prime candidate for providing a wake-up signal 118 when it iswritten to by the user interaction device 120.

This configurability can be achieved by the host processor 112 writingconfiguration parameters into a special area of the non-volatile memory104 by means of the host connection 116. For example, this special areacould contain bitmaps indicating which areas of the non-volatile memory104 must cause a wake-up when addressed for reading and/or writing, andwhich areas must not cause a wake-up. Control logic in the Connected Tag102 will interpret the configuration parameters to decide whether or notto trigger the wake-up signal 118 upon addressing a specific memorycell.

For example, if the controlled device is a washing machine, thendifferent settings can be programmed without wake-up, for example thetemperature and the washing program. However, when the “start program”button is pushed on the user interaction device 120—or when a timer isprogrammed to start the washing machine at a certain moment in time—awake-up is necessary.

According to another example, if the controlled device 100 is anenergy-frugal sensor node it may not be necessary to wake it up when theoperational parameters are typical configuration settings which need tobe programmed into it—such as the set of physical quantities to measureand the associated measurement accuracies—or when the operationalparameters consist of actual measurements of slowly changing physicalphenomena which need to be checked—such as the room temperature.However, it may be necessary to wake it up when the operationalparameters consist of measurements of quickly changing physicalphenomena—such as a lighting level—or when it is enabled for duty-cycledoperation for the first time. In this case it is assumed that theenergy-frugal sensor node wakes up periodically to performmeasurements—and log the results thereof in the non-volatile memory 104and/or transmit them over a wireless interface—and that the slowlychanging phenomena show little change during a single period, whereasthe quickly changing phenomena may show a lot of change during a singleperiod.

Operational Parameters Include a User Interface Description

The operational parameters supplied by the controlled device 100 to theuser interaction device 120 as part of step (2) of a method of the kindset forth may comprise a user interface description in addition to—oreffectively embedding—operational parameters that directly relate to thefunctioning of the controlled device 100. For the sake of clarity, thelatter are called function parameters in this section.

For example, an HTML-page containing the function parameters as (defaultsettings for) e.g. radio button selectors, check boxes, and/or pull downmenu controls may be provided as operational parameter. In step (3), theuser interaction device 120 will load this HTML-page into anHTML-renderer application enabling the end-user to modify the variouscontrols (and hence the function parameters). The HTML-rendererapplication is very similar to an Internet browser, but the protocols tocommunicate with the Connected Tag 102 may be different from plain HTTP.For example, the HTML-renderer application may be realized by means of astandard browser and an embedded web server that converts thoseprotocols to/from HTTP. After the end-user has finished modifying thecontrols, the function parameters must be “posted” back to thecontrolled device 100 as part of step (4). This action of “posting” thefunction parameters can be triggered by a “submit” button on theHTML-page or, alternatively, by the end-user bringing the userinteraction device 120 into close proximity of the controlled device100. In the former case, the end-user needs to press the “submit” buttonwhile the user interaction device 120 is in close proximity of thecontrolled device 100. A combination of the two is also possible: eitherthe end-user pressing the “submit” button in close proximity, or theend-user first pressing the “submit” button and subsequently bringingthe user interaction device 120 into close proximity again.

The benefit of including a user interface description in the operationalparameters is the ability to have a dedicated user interface 126 foreach type of controlled device 100. The user interaction device 120requires no a priori knowledge of the controlled device 100 and yet isable to provide an optimally tailored user interface 126 for it to theend-user. In other words, it is not necessary to install a different“app” on the user interaction device 120 for each different type ofcontrolled device 100. Instead, a single generic (protocol-adapted)browser suffices, such that the browser may be standardized. The userinterface 126 could also be branded by the manufacturer of thecontrolled device 100. Alternatively, or in addition, the user interfacedescription may comprise client-executable code such as JavaScript, CSS,Java or Adobe Flash—stored as additional files on the Connected Tag102—offering a more dynamic (e.g. animated) user interface experienceand/or the possibility to compute function parameters from moreuser-friendly settings. For example, a temperature setting on the userinterface 126 for a washing machine may be in Celsius or Fahrenheit,while the parameters accepted by the washing machine are in yet anotherunit of measurement.

As a variant, the user interface description may be provided byreference, for example by the controlled device 100 providing a URLpointing to a user interface description—instead of the user interfacedescription itself—as part of the operational parameters. In this case,the user interaction device 120 furthermore needs to comprise Internetaccess means, for example, a Wi-Fi radio or a GPRS/UMTS modem. This istypically the case when the user interaction device 120 is a smart phoneor a web tablet. In this variant, the user interaction device 120 usesthe URL thus obtained to retrieve the actual user interface descriptionutilizing the Internet access means and subsequently presents a userinterface 126 in accordance with this description to the end-user (afterwhich the method proceeds as outlined above). The benefit of thisvariant is that the non-volatile memory 104 of the Connected Tag 102needs to provide less data (a URL typically being much smaller than auser interface description) reducing the cost of the controlled device100 and possibly also the download time of the user interfacedescription. As this effectively removes any size constraint on the userinterface description, the user interface description could even be adedicated application that is automatically downloaded and installed onthe user interaction device 120. Another benefit is that themanufacturer of the controlled device 100 can easily update the userinterface description by providing a new version on his website. It isnoted that in this example it is assumed that the URL points to thewebsite of the manufacturer.

It is also noted that multiple message exchanges between the controlleddevice 100 and the user interaction device 120 may take place as part ofa single user interaction session. This means that once a user interfacedescription (and possibly initial function parameters) have beenobtained from the controlled device 100 in a first step (2), the userinteraction device 120 may go through steps (2), (3), and (4) of themethod more than once and the controlled device 100 may be involved insteps (1), (2), (4) and (5) more than once. In subsequent iterations,the user interface description may remain the same, or it may change(e.g. browse to new HTML-pages to obtain submenus). The point of this isthat some state information (in this case a user interface descriptionwith actual settings for the function parameters) may be maintained bythe user interaction device 120 while performing the method multipletimes.

Furthermore, it is noted that the user interaction device 120 may cachethe user interface description, so that it is not necessary to downloadit (from the controlled device 100 or from the Internet) each and everytime that interaction with the controlled device 100 is needed. Uponreading the operational parameters from the controlled device 100, theuser interaction device 120 obtains a unique identifier of the userinterface description (in the variant above this is the URL) and checkswhether it has already downloaded a user interface description with thisunique identifier. Only if it has not, it will download the userinterface description.

Many application examples can be imagined. For any of the exemplaryapplications described above (energy-frugal sensor node, householdappliance, time-controlled electric plug, and electronic watch) it wouldbe beneficial to have a dedicated user interface.

Yet another example is a pin-code lock for, for example, a scooter. Theuser interaction device 120 (for example a smart phone) obtains a userinterface description from the scooter through the Connected Tag 102.This user interface description supports the pin-code entry and writesthe entered pin-code back into the Connected Tag 102. The scooter iswoken up by writing into the Connected Tag 102 (see section “Wake uphost controller during or following interaction”). Subsequently, thescooter verifies the pin-code and releases the lock if the pin-code iscorrect. It is noted that in this case the user interface description isthe only operational parameter read from the controlled device 100 (i.e.the scooter); no function parameters are read and only one functionparameter is written (i.e. the pin-code). However, a more securesolution involves using a public/private key pair (i.e. public keycryptography). The smart phone first reads a user interface descriptionand a public key from the scooter, in particular from its Connected Tag102, subsequently uses the user interface 126 to obtain the pin-codefrom the end-user, encrypts the pin-code with the public key and writesit back to the scooter, in particular to its Connected Tag 102. TheConnected Tag 102 wakes up the scooter, which first decrypts thepin-code with its private key. Subsequently the scooter verifies thepin-code, and if the pin-code is correct the scooter releases the lock.

The above-mentioned embodiments illustrate rather than limit theinvention, and the skilled person will be able to design manyalternative embodiments without departing from the scope of the appendedclaims. In the claims, any reference sign placed between parenthesesshall not be construed as limiting the claim. The word “comprise(s)” or“comprising” does not exclude the presence of elements or steps otherthan those listed in a claim. The word “a” or “an” preceding an elementdoes not exclude the presence of a plurality of such elements. Theinvention may be implemented by means of hardware comprising severaldistinct elements and/or by means of a suitably programmed processor. Ina device claim enumerating several means, several of these means may beembodied by one and the same item of hardware. The mere fact thatcertain measures are recited in mutually different dependent claims doesnot indicate that a combination of these measures cannot be used toadvantage.

LIST OF REFERENCE SIGNS

-   100 controlled device-   102 RFID tag-   104 non-volatile memory-   106 RFID interface-   108 tag controller-   110 host memory-   112 host controller-   114 controlled functions-   116 host connection-   118 optional wake-up signal-   120 user interaction device-   122 NFC interface device or active RFID device-   124 controller-   126 user interface-   128 memory-   130 RFID connection-   200 “waiting for request” state-   202 “request parameters” state-   204 “parameters available” state-   206 “parameters updated” state-   208 initialize-   210 first state transition-   212 second state transition-   214 third state transition-   216 fourth state transition

The invention claimed is:
 1. A method for controlling a controlleddevice, wherein the controlled device comprises an RFID tag and a hostcontroller, wherein the RFID tag is connected to the host controller viaa wired host connection, the method comprising the following steps: (s1)the host controller writes operational parameters to the RFID tagthrough the host connection; (s2) a user interaction device reads theoperational parameters from the RFID tag through an RFID connection;(s3) a user changes the operational parameters via a user interfacecomprised in the user interaction device; (s4) the user interactiondevice writes the operational parameters to the RFID tag through theRFID connection; (s5) the host controller reads the operationalparameters from the RFID tag through the host connection and adapts thebehavior of the controlled device by configuring a set of controlledfunctions based on the operational parameter; wherein the RFID tag sendsa wake-up signal to the controlled device upon a predetermined event,such that the controlled device wakes up from an off state or low-powerstate; wherein a handshake protocol is executed between the userinteraction device and the controlled device via the RFID tag, such thatthe controlled device may return to the off state or low-power state ifit does not need to perform a step of the method; wherein the handshakeprotocol comprises that the user interaction device changes a signalingflag comprised in the RFID tag; wherein the signaling flag indicateswhether or not the controlled device needs to perform a specific step ofthe method; wherein, upon waking up, the controlled device reads thesignaling flag and returns to the off state or low-power state if thesignaling flag indicates that it does not need to perform any specificstep of the method.
 2. A method as claimed in claim 1, wherein thepredetermined event is a detection of an RF field by the RFID tag or theestablishment of the RFID connection.
 3. A method as claimed in claim 1,wherein the predetermined event is the writing of the operationalparameters to the RFID tag in step (s4) or the disappearance of the RFfield or the RFID connection in step (s4).
 4. A method as claimed inclaim 1, wherein the RFID tag only provides the wake-up signal to thecontrolled device if predetermined sections of a memory comprised in theRFID tag are read from and/or written to by the user interaction device;wherein the predetermined sections of the memory contain operationalparameters relating to operations that require a wake-up of thecontrolled device.
 5. A method as claimed in claim 4, wherein theoperational parameters include a description of the user interfacecomprised in the user interaction device.
 6. A method as claimed inclaim 5, wherein the description of the user interface embedsoperational parameters which directly relate to the functioning of thecontrolled device.
 7. A method as claimed in claim 5, wherein thedescription of the user interface is provided by reference, inparticular by a URL pointing to a website from which the description ofthe user interface is retrievable.
 8. A method for controlling acontrolled device, wherein the controlled device comprises an RFID tagand a host controller, wherein the RFID tag is connected to the hostcontroller via a wired host connection, the method comprising thefollowing steps: (s1) the host controller writes operational parametersto the RFID tag through the host connection; (s2) a user interactiondevice reads the operational parameters from the RFID tag through anRFID connection; (s3) a user changes the operational parameters via auser interface comprised in the user interaction device; (s4) the userinteraction device writes the operational parameters to the RFID tagthrough the RFID connection; (s5) the host controller reads theoperational parameters from the RFID tag through the host connection andadapts the behavior of the controlled device by configuring a set ofcontrolled functions based on the operational parameter; wherein theRFID tag sends a wake-up signal to the controlled device upon apredetermined event, such that the controlled device wakes up from anoff state or low-power state, wherein the predetermined event is thedisappearance of the RF field or the disappearance of the RFIDconnection in step (s4).